1. You and a friend are hiking through a canyon. You tell your friend that the rock layers in the canyon are all different ages, and you can tell which rock layers are the oldest and which are the youngest. She picks four different rock layers on the canyon wall, as shown in the
photograph
Which layer is the youngest?

A. Layer 1
O B. Layer 2
C. Layer 3
D. Layer 4

Arock can be broken down into different kinds of substances by physical processes. no chemical reactions are needed to separate different parts of a rock into pure substances. this is because a rock is a(n)

Select the correct value for the indicated bond angle in each of the compounds. o−o−oo−o−o angle of o3 90° 109.5° < 109.5° 120° < 120° 180° f−b−ff−b−f angle of bf3 180° < 109.5° < 120° 120° 109.5° 90° f−o−ff−o−f angle of of2 < 120° 120° 90° 109.5° 180° < 109.5° cl−be−clcl−be−cl angle of becl2 90° 109.5° 180° 120° < 109.5° < 120° f−p−ff−p−f angle of pf3 90° 109.5° < 109.5° 180° 120° < 120° h−c−hh−c−h angle of ch4 90° < 109.5° 180° 120° < 120° 109.5°

Heat energy, carbon dioxide, and water are released through which process? a. photosynthesis b. depolymerization c. digestion d. cellular respiration